Models of the demographic processes of fertility, nuptiality, and mortality have proved useful in many ways including (1) concise description of complex structures of vital events, (2) smoothing of outlying values or interpolation between sparse values, (3) population projection, and (4) building blocks for methods of estimating basic demographic characteristics from inaccurate or incomplete data. We plan to build slightly more complex but more realistic models of age patterns of marriage, divorce, fertility, and mortality in order to improve the usefulness of current models. In addition, we plan to use these new models to test and refine current methods of estimation and to propose new methods which utilize logical and empirical interrelationships among demographic variables.